复合材料层合板损伤区域扩展全过程分析

对碳纤维NCF层合板进行了2组准静态压痕试验。第1组采用不同的压头尺寸探究不同压头直径对层合板损伤区域和面积的影响;第2组进行固定压头尺寸的重复试验,使用非接触空气耦合超声波扫描试样损伤情况,研究静压痕力、凹坑深度、损伤面积三者之间的联系。利用Abaqus有限元软件,根据Hashin准则和内聚力单元的结合,对第2组层合板准静态压痕试验进行全过程的损伤扩展分析。分析结果表明,基体拉伸的破坏是层合板最容易出现的破坏,而且其损伤区域涵盖了其他4种损伤区域。凹坑深度与损伤面积存在一定联系,试验开始阶段凹坑增加速度缓慢,损伤面积增加速度较快;接近极限载荷时,凹坑深度增加速度加快,损伤面积增加速度减缓。

THE WHOLE PROCESS ANALYSIS OF DAMAGE AREA EXPANSION OF COMPOSITE LAMINATES

Two groups of quasi-static indentation tests were carried out on carbon fiber NCF laminates.In the first group,the influence of different head diameter on the damage area was studied by using different indenter sizes.In the second group,the repeated test of fixed head size was carried out to study the relationship between the static indentation force,the dent depth and the damage area by using the non-contact air-coupled ultrasonic scanning sample.Based on the Hashin criterion and the cohesive element,the whole process damage propagation analysis of the second groups of laminates was carried out by using Abaqus software.The results indicate that the tensile failure of matrix is the most easily damaged,and the damage area covers the other 4 kinds of damage areas.There is a connection between dent depth and damage area.At the beginning of the test,the dent depth increases slowly,the damage area increases fast;close to the ultimate load,the dent depth increases fast,the damage area increases slowly.